#include<iostream>
#include<set>
#include<vector>
using namespace std;

void printSet(const set<int>& s){
        for(set<int>::const_iterator it=s.begin(); it!=s.end(); it++){
                cout<<*it<<" ";
        }
        cout<<endl;
}

int main(){


	set<int> s={1,2,3,4,5};

	set<int>::iterator it=s.find(3);

	if(it!=s.end()){
		cout<<"find: "<<(*it)<<endl;
	}

	it=s.find(10);
	if(it==s.end()){
		cout<<"can't find : 10"<<endl;
	}
	return 0;
}
